The invention pertains to an electronic device as well as to a plate for this electronic device.
The performance of an electronic device often depends on the capacity to cool it efficiently. To this end, a prior-art electronic device comprise:                at least one heat-generating heat source,        at least one cold point capable of absorbing heat,        a thermally insulating material of which the thermal conductivity at the temperature of use Tf of the device is below a threshold S1, this material thermally insulating the heat source from the cold point, and        at least one thermal bridge extending between at least two ends thermally connected respectively to the heat source and to the cold point.        
The term “temperature of use” is understood to mean the average temperature of the environment in which the electronic device works.
In these prior-art electronic devices, the thermal bridge is typically at least one track made out of metal or out of a semiconducting material that extends continuously from one end to the other. Such thermal bridges enable the flow of heat to be directed from the heat source to the cold point and therefore to improve the cooling of the electronic device. In several prior-art electronic devices, the thermal bridge is non-existent or has little efficiency.
The heat source may be any unspecified heat-dissipating electronic module, for example capacitor-based and inductor-based resistors or oscillators. However, the heat source is often an electronic module made with transistors. In the prior-art electronic devices, especially nomad electronic devices, the activity of an electronic module can vary greatly. For example, an electronic module can pass from an inactive state in which it is not powered or little used towards an active state in which it is highly used. In the inactive state it produces no heat or relatively little heat. Conversely, in the active state, it can produce a lot of heat, thus causing a great increase in its temperature.
Thus, in electronic devices of this kind, the heat source is not always at the same place. Furthermore, depending on the activity of the electronic device, the electronic module to be cooled as a priority is not always the same.
Known thermal bridges do not allow for a satisfactory response to these changes in the operating condition of the electronic device. In this respect, they show low efficiency in distributing heat efficiently in the electronic device. The prior art is also known from:
US2009/040007 A1,
U.S. Pat. No. 5,867,990 A,
U.S. Pat. No. 6,301,114 B1,
U.S. Pat. No. 4,402,358 A,
US2006/066434 A1,
U.S. Pat. No. 4,742,867 A.